1. Field of the Invention.
The present invention relates generally to automatic envelope stuffing equipment, and in particular to an improved hopper for converting such equipment for use with envelopes having latex seal adhesive.
2. Description of the Prior Art.
In businesses and institutions which routinely send out large quantities of mail, automatic envelope stuffing equipment is often utilized to facilitate such mass mailings. For example, in the banking industry it is common practice to mail each customer monthly statements of account. In addition to summarizing various account transactions for the preceding month, such statements are often accompanied by the cancelled checks received by the bank during the preceding month. Many banks employ automatic envelope stuffing equipment to insert statements and cancelled checks in envelopes for mailing to their customers.
Previous automatic envelope stuffing equipment was generally designed for use with remoistenable adhesive envelopes. For example, the Sather et al. U.S. Pat. No. 3,368,321 shows an inserter with a moistener assembly for moistening the gum or mucilage on the envelope flaps for sealing. In the Sather inserter, an envelope supply magazine station is provided wherein envelopes are stacked with their flaps in their closed positions. The remoistenable adhesive of such envelopes will not stick or adhere until moistened, hence the envelopes can be stored in such positions. The hoppers for remoistenable adhesive envelopes generally included a plurality of upright rods or plates which partially enclosed a space adapted to receive a stack of envelopes. For example, the plates in the Sather et al. inserter confine a stack of envelopes in the envelope supply magazine station.
Latex adhesive for envelopes has achieved substantial popularity because the adhesive surfaces to be joined are merely pressed together whereby the moistening step in the process and the attendant necessary equipment are obviated. Since such equipment tended to be somewhat messy and required a continuous water supply, the use of latex adhesive on the envelopes can make automatic envelope stuffing processes cleaner and simpler.
However, a disadvantage to the use of latex adhesive envelopes relates directly to their advantage, i.e. that their adhesive surfaces will stick together on contact. Thus, the seal flaps of latex adhesive envelopes generally must be in their open positions when such envelopes are stacked, as in automatic insertion equipment. This requirement has heretofore rendered many previous envelope stuffing machines unsuitable for use with latex adhesive envelopes, because their hoppers were designed to handle only envelopes with their seal flaps folded shut. Heretofore, there were relatively few, if any, automatic inserting machines adapted for interchangeable use with both remoistenable and latex adhesive envelopes or even with latex adhesive envelopes only, in spite of the advantages of such envelopes.
The present invention addresses this problem.